Excavation bucket assemblies are used in the construction and mining. The bucket assemblies are used with a variety of different excavating apparatuses such as backhoes, power shovels, front-end loaders, dragline equipment, etc. Excavation bucket assemblies typically have a bucket body with a rear wall, sidewalls, and a bottom wall. The walls cooperatively define a region where excavated material can be contained and moved. The bottom, front edge of the bucket body can be coupled to a lip. Tooth assemblies are coupled to the lip to form an excavation bucket assembly.
Each tooth assembly can include an adaptor and a tooth. The adaptor can be coupled to the lip and a tooth can be coupled to the adaptor. Pins can be used to couple the parts of the tooth assembly together and can be used to couple the tooth assembly to the lip. When a tooth becomes worn or damaged, the pin coupling the tooth to its corresponding adapter can be removed so that the tooth can be uncoupled from the adaptor. A new tooth is then mounted in the place of the worn or damaged tooth.
During the tooth replacement process, the pin is knocked out with a large hammer. If the pin is damaged during this process, it is replaced with a new pin. Frequently replacing broken pins is undesirable as doing so increases the cost of maintaining the excavation bucket assembly. Moreover, using a large hammer to remove a pin can be dangerous. When striking the pin with a hammer, flying debris such as metal chips and sand can be created. The flying debris can potentially harm persons in the vicinity of the hammering.
An improvement over the conventional pin-based coupling systems is described in U.S. Pat. No. 6,216,368 by the same inventor as the present invention. FIG. 1 shows an embodiment in the U.S. patent. FIG. 1 shows the wedge-locking system 101 that couples an adaptor 106 and a tooth 105 together without the use of pins. Other details about the wedge-locking system 101 are described in the U.S. patent, which is herein incorporated by reference in its entirety for all purposes. As shown in FIG. 1, the wedge-locking system 101 is present in a depression 102 in the adaptor 106. In this example, the depression 102 is in the form of a rectangle and is defined by four slightly raised walls.
Over a period of time, particles such as grit or sand can get into the depression 102 and can abrade the parts of the wedge-locking system 101 and the adaptor 106. Accordingly, when the operator uncouples the adaptor 106 and the tooth 105, the operator also cleans the depression 102 of sand and grit. If the operator does not clean the depression 102 well, particles can remain in the depression 102. When the wedge-locking system 101 is in use, the particles lodged in the depression 102 can continue to abrade the parts of the wedge-locking system 101 and the adaptor 106. The abrasion reduces the useful life of the wedge-locking system 101 and the adaptor 106. More frequent replacement of the wedge-locking system 101 parts and the adaptor 106 may be required.
Embodiments of the invention address these and other problems.
One embodiment of the invention is directed to a locking system for coupling a first member including an aperture, and a second member having a receiving region, the locking system comprising: (a) an interference element including (i) a first portion that fits within the aperture of the first member when the locking system couples the first member and the second member together, and (ii) a second portion, wherein the first portion forms an angle with respect to the second portion, and (iii) a protrusion that extends into the receiving region of the second member when the locking system is in use; and (b) a locking element that engages the second portion of the interference element when the locking system is in use.
Another embodiment of the invention is directed to an assembly comprising: a first member including an aperture; a second member having a receiving region and a recess; and a locking system that couples the first member to the second member, wherein the locking system comprises (a) an interference element including (i) a first portion disposed within the aperture of the first member, (ii) a second portion, wherein the first portion forms an angle with respect to the second portion, and (iii) a protrusion that extends into the receiving region of the second member, and (b) a locking element that engages the second portion of the interference element and that is in the recess.
Another embodiment of the invention is directed to an excavation bucket assembly comprising: a bucket body; and a plurality of tooth assemblies coupled to the bucket body, wherein each tooth assembly includes an adaptor including an aperture, a tooth having a receiving region, and a locking system that couples the first member to the second member, wherein the locking system comprises (a) an interference element including (i) a first portion disposed within the aperture of the first member, and (ii) a second portion, wherein the first portion forms an angle with respect to the second portion, and (iii) a protrusion that extends into the receiving region, and (b) a locking element that engages the second portion of the interference element.